Sohmer H, Freeman S, Friedman I, Lidan D
Department of Physiology, Hebrew University, Hadassah Medical School, Jerusalem, Israel.
Acta Otolaryngol. 1991;111(2):206-11. doi: 10.3109/00016489109137376.
Clinical ABR studies in patients with peripheral hearing loss have led to conflicting results, some reporting increases in brainstem transmission time (BTT), some decreases, and others no change. In order to study this in a carefully controlled fashion, various types of peripheral hearing losses were induced in experimental animals: conductive hearing loss by occluding auditory meatus (rats) (CHL), noise induced temporary sensori-neural hearing loss (rats) (NI-SNHL), stimulus intensity attenuation (rats), (Atten.), and controlled hypoxemia induced temporary sensori-neural hearing loss (cats) (HI-SNHL). ABR latencies and thresholds were determined in each animal before (control) and during the induced hearing loss (experimental) states. The data in each group in each state were analyzed by calculating group average values for latency of waves 1 and 4, their interpeak latency (BTT), paired t-tests for changes between the control and experimental states and linear regression analysis of latency changes on threshold shift. In each group, there were small decreases in BTT in the experimental state (not significant in the CHL group only). This was caused by the prolongation of latency of wave 1 to a greater extent than that of wave 4. These changes were smaller than the standard deviation of the BTT in the control state. Therefore, in attempting to apply these results to the human clinical situation, these small decreases in BTT would not be considered abnormal. Possible mechanisms of these BTT changes are considered.
针对外周性听力损失患者的临床听性脑干反应（ABR）研究结果相互矛盾，一些报告称脑干传导时间（BTT）增加，一些报告称减少，还有一些报告称无变化。为了以严格可控的方式对此进行研究，在实验动物中诱发了各种类型的外周性听力损失：通过堵塞耳道诱发传导性听力损失（大鼠）（CHL）、噪声诱发的暂时性感音神经性听力损失（大鼠）（NI-SNHL）、刺激强度衰减（大鼠）（Atten.）以及控制性低氧血症诱发的暂时性感音神经性听力损失（猫）（HI-SNHL）。在每只动物处于诱发听力损失之前（对照）和期间（实验）测定ABR潜伏期和阈值。通过计算第1波和第4波潜伏期的组平均值、它们的峰间潜伏期（BTT）、对照状态和实验状态之间变化的配对t检验以及潜伏期变化对阈值偏移的线性回归分析，对每种状态下每组的数据进行分析。在每组中，实验状态下BTT有小幅下降（仅在CHL组中不显著）。这是由于第1波潜伏期的延长程度大于第4波。这些变化小于对照状态下BTT的标准差。因此，在试图将这些结果应用于人类临床情况时，BTT的这些小幅下降不会被视为异常。文中还考虑了这些BTT变化的可能机制。
